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		<updated>2026-05-15T19:42:21Z</updated>
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	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3181:_Jumping_Frog_Radius&amp;diff=401896</id>
		<title>Talk:3181: Jumping Frog Radius</title>
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				<updated>2025-12-16T10:16:51Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: &lt;/p&gt;
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&lt;div&gt;&amp;lt;!-- Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom. --&amp;gt;&lt;br /&gt;
first[[User:Qwertyuiopfromdefly|Qwertyuiopfromdefly]] ([[User talk:Qwertyuiopfromdefly|talk]]) 05:17, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
Question: Would a correct interpretation be &amp;quot;if a champion jumping frog were to be located just under 1.5 light-days from earth, and if there we're no other gravitational bodies nearby, and if said frog then performed its mightiest jump directly away from earth, then the frog would eventually be overcome by Earth's gravitational field and would eventually land on Earth's surface&amp;quot;? [[User:Pgn674|Pgn674]] ([[User talk:Pgn674|talk]]) 06:26, 16 December 2025 (UTC)&lt;br /&gt;
:I guess that is exactly how it should be interpreted. Or more interesting if it was just outside this radius and somehow could gain exactly 4,5 m/s extra speed then it would escape Earth (if there was anything to push of against that was heavy enough to move basically only the frog forward, then that would change the mass behind the frog so... That was why I wrote gain exactly rather than jump).  --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 07:36, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
: or its mightiest jump in any direction (that doesn't cause it to crash through the Earth) since the escape speed is the same in all directions (relevant xkcd:https://what-if.xkcd.com/68/ ) --[[Special:Contributions/178.197.223.163|178.197.223.163]] 09:21, 16 December 2025 (UTC)&lt;br /&gt;
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[[User:Zabadoh|Zabadoh]] ([[User talk:Zabadoh|talk]]) 08:20, 16 December 2025 (UTC)The only two variables are rjf and M, so plotting a 2 axis graph plotting the relationship between M and rjf should be possible.&lt;br /&gt;
&lt;br /&gt;
As frogs usually collect on the surface of worlds {{cn}}, the *surface* escape velocity is most important. The crossover point for a planet with earth-like density (5515 kg/m³) is 2.6km, above that, the rjf falls below the surface, and the planet can accumulate frogs. Smaller bodies are, however, usually less dense; an interesting borderline candidate is Chicxulub,  which had an rjf of 3-4km, and a radius of 5-6km so could have just about held onto its frogs, for a while at least. [[User:JeffUK|JeffUK]] ([[User talk:JeffUK|talk]]) 10:04, 16 December 2025 (UTC)&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3181:_Jumping_Frog_Radius&amp;diff=401895</id>
		<title>Talk:3181: Jumping Frog Radius</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3181:_Jumping_Frog_Radius&amp;diff=401895"/>
				<updated>2025-12-16T10:04:28Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: &lt;/p&gt;
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&lt;div&gt;&amp;lt;!-- Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom. --&amp;gt;&lt;br /&gt;
first[[User:Qwertyuiopfromdefly|Qwertyuiopfromdefly]] ([[User talk:Qwertyuiopfromdefly|talk]]) 05:17, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
Question: Would a correct interpretation be &amp;quot;if a champion jumping frog were to be located just under 1.5 light-days from earth, and if there we're no other gravitational bodies nearby, and if said frog then performed its mightiest jump directly away from earth, then the frog would eventually be overcome by Earth's gravitational field and would eventually land on Earth's surface&amp;quot;? [[User:Pgn674|Pgn674]] ([[User talk:Pgn674|talk]]) 06:26, 16 December 2025 (UTC)&lt;br /&gt;
:I guess that is exactly how it should be interpreted. Or more interesting if it was just outside this radius and somehow could gain exactly 4,5 m/s extra speed then it would escape Earth (if there was anything to push of against that was heavy enough to move basically only the frog forward, then that would change the mass behind the frog so... That was why I wrote gain exactly rather than jump).  --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 07:36, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
: or its mightiest jump in any direction (that doesn't cause it to crash through the Earth) since the escape speed is the same in all directions (relevant xkcd:https://what-if.xkcd.com/68/ ) --[[Special:Contributions/178.197.223.163|178.197.223.163]] 09:21, 16 December 2025 (UTC)&lt;br /&gt;
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[[User:Zabadoh|Zabadoh]] ([[User talk:Zabadoh|talk]]) 08:20, 16 December 2025 (UTC)The only two variables are rjf and M, so plotting a 2 axis graph plotting the relationship between M and rjf should be possible.&lt;br /&gt;
&lt;br /&gt;
As frogs usually collect on the surface of worlds {{cn}}, the *surface* escape velocity is most important. The crossover point for a planet with earth-like density (5515 kg/m³) is 2.6km, above that, the rjf falls below the surface, and the planet can accumulate frogs. [[User:JeffUK|JeffUK]] ([[User talk:JeffUK|talk]]) 10:04, 16 December 2025 (UTC)&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3181:_Jumping_Frog_Radius&amp;diff=401894</id>
		<title>Talk:3181: Jumping Frog Radius</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3181:_Jumping_Frog_Radius&amp;diff=401894"/>
				<updated>2025-12-16T10:04:05Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: Reply&lt;/p&gt;
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&lt;div&gt;&amp;lt;!-- Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom. --&amp;gt;&lt;br /&gt;
first[[User:Qwertyuiopfromdefly|Qwertyuiopfromdefly]] ([[User talk:Qwertyuiopfromdefly|talk]]) 05:17, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
Question: Would a correct interpretation be &amp;quot;if a champion jumping frog were to be located just under 1.5 light-days from earth, and if there we're no other gravitational bodies nearby, and if said frog then performed its mightiest jump directly away from earth, then the frog would eventually be overcome by Earth's gravitational field and would eventually land on Earth's surface&amp;quot;? [[User:Pgn674|Pgn674]] ([[User talk:Pgn674|talk]]) 06:26, 16 December 2025 (UTC)&lt;br /&gt;
:I guess that is exactly how it should be interpreted. Or more interesting if it was just outside this radius and somehow could gain exactly 4,5 m/s extra speed then it would escape Earth (if there was anything to push of against that was heavy enough to move basically only the frog forward, then that would change the mass behind the frog so... That was why I wrote gain exactly rather than jump).  --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 07:36, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
: or its mightiest jump in any direction (that doesn't cause it to crash through the Earth) since the escape speed is the same in all directions (relevant xkcd:https://what-if.xkcd.com/68/ ) --[[Special:Contributions/178.197.223.163|178.197.223.163]] 09:21, 16 December 2025 (UTC)&lt;br /&gt;
&lt;br /&gt;
[[User:Zabadoh|Zabadoh]] ([[User talk:Zabadoh|talk]]) 08:20, 16 December 2025 (UTC)The only two variables are rjf and M, so plotting a 2 axis graph plotting the relationship between M and rjf should be possible.&lt;br /&gt;
&lt;br /&gt;
As frogs usually collect on the surface of worlds {{cn}}, the *surface* escape velocity is most important. The crossover point for a planet with earth-like density (5515 kg/m³) is 2.6km, above that, the JFR falls below the surface, and the planet can accumulate frogs. [[User:JeffUK|JeffUK]] ([[User talk:JeffUK|talk]]) 10:04, 16 December 2025 (UTC)&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3036:_Chess_Zoo&amp;diff=361890</id>
		<title>Talk:3036: Chess Zoo</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3036:_Chess_Zoo&amp;diff=361890"/>
				<updated>2025-01-13T11:24:28Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: &lt;/p&gt;
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&lt;div&gt;&amp;lt;!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--&amp;gt;&lt;br /&gt;
For the transcript, I’m thinking of saying that “there are alternating white and grey squares, with smaller black squares imposed on them. The pattern of squares goes ''[something like GWBWGWBWGBW]''“. Would that work? Or is it too confusing? '''[[User:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:9pt;color:#A9C6CA&amp;quot;&amp;gt;42.book.addict&amp;lt;/span&amp;gt;]]&amp;lt;sup&amp;gt;[[User talk:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:6pt;color:#516874&amp;quot;&amp;gt;Talk to me!&amp;lt;/span&amp;gt;]]&amp;lt;/sup&amp;gt;''' 19:03, 10 January 2025 (UTC)&lt;br /&gt;
:Re: &amp;quot;GWBWGWBWGBW&amp;quot;, knowing who we are here, I presume people might want to distinguish black-on-white from black-on-gray. We'd probably have to have a full markup system for background (gray/white) and foreground (empty, human, barrier, white pawn, gray pawn...). Maybe something like {[gE][wE][gB][wQg]}... Hrm... Because, of course, it has to be as complicated and precise as possible. :) [[Special:Contributions/172.70.46.135|172.70.46.135]] 19:15, 10 January 2025 (UTC)&lt;br /&gt;
::I don’t really like the current transcript because I believe that it’s more confusing to read than my version. Anyone have thoughts? '''[[User:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:9pt;color:#A9C6CA&amp;quot;&amp;gt;42.book.addict&amp;lt;/span&amp;gt;]]&amp;lt;sup&amp;gt;[[User talk:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:6pt;color:#516874&amp;quot;&amp;gt;Talk to me!&amp;lt;/span&amp;gt;]]&amp;lt;/sup&amp;gt;''' 23:28, 10 January 2025 (UTC)&lt;br /&gt;
:::Although I do have a suggestion for the transcript: instead of having “H” as a representation of a human, we can have C for [[Cueball]], H for [[Hairy]], P for [[Ponytail]], W for [[White Hat]], D for [[Danish]], M for [[Megan]], and K for [[Knit Cap]]. We could also have Unicode black squares instead of the “#” and color the pieces with span. Thoughts? '''[[User:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:9pt;color:#A9C6CA&amp;quot;&amp;gt;42.book.addict&amp;lt;/span&amp;gt;]]&amp;lt;sup&amp;gt;[[User talk:42.book.addict|&amp;lt;span style=&amp;quot;font-family:Cormorant Garamond;font-size:6pt;color:#516874&amp;quot;&amp;gt;Talk to me!&amp;lt;/span&amp;gt;]]&amp;lt;/sup&amp;gt;''' 00:14, 11 January 2025 (UTC)&lt;br /&gt;
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I don't think it's safe to allow people to go into the bishop enclosure, especially with high aggression in that area since both colors are able to look at each other there but not capture. One of those bishops is eventually going to take it out on someone. --[[Special:Contributions/162.158.90.210|162.158.90.210]] 19:34, 10 January 2025 (UTC)&lt;br /&gt;
:I don't know how dangerous they are to visitors in general, but I wouldn't leave children with them unattended. Maybe the enclosures with the knights would be good petting zoos. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 19:49, 10 January 2025 (UTC)&lt;br /&gt;
:Thank you for reporting the bishop feeding gate being open, as this was the fifteenth time the one responsible failed to close it after feeding, he has been summarily fired.[[Special:Contributions/172.70.47.106|172.70.47.106]] 20:02, 10 January 2025 (UTC)&lt;br /&gt;
The zoo seems to be missing an area for knights and bishops to interact.  (It has a knight/queen area, a knight/rook area, and a rook/bishop area. It can't have queen/rook or queen/bishop areas if it wants to have areas for rooks or bishops that exclude queens, because nothing blocks queens without blocking rooks and bishops. But it could have a knight/bishop mingling area, accessible to knights via wall-jump and to bishops via a diagonal corridor, and it doesn't.) [[Special:Contributions/162.158.187.84|162.158.187.84]] 20:07, 10 January 2025 (UTC)&lt;br /&gt;
:Similarly, couldn't the pawn promoting zones be more centrally located each side, and have passages respectively for queens/rooks and for knights? Of course then those could enter and interact with promoting pawns, but why would that be deemed a problem? --[[Special:Contributions/172.69.222.164|172.69.222.164]] 20:41, 10 January 2025 (UTC)&lt;br /&gt;
::No because it a promoted queen can come into a zone with rooks then it can also get into the bishops room and then enter the opposing bishops room and take them and then get to take opposing rooks and knights as well. It would also be hard to keep knight's out of the opposing side if they get into the bishops area, it would take a lot of wall space. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 10:52, 12 January 2025 (UTC)&lt;br /&gt;
:I believe a knight-knight interaction zone of opposing colors is also possible if correctly designed (such as a 2xn corridor with a particular entrance [[Special:Contributions/162.158.154.52|162.158.154.52]] 03:11, 11 January 2025 (UTC)&lt;br /&gt;
::It would have to be a very restrictive zone. In the case of the 3x3 of [[839: Explorers]], any knight not on the centre-tile could technically take (or be taken by) any other such knight of that was also there (and not on the centre-tile). Though any knight in imminent danger could of course move to not be (the knight that posed the danger could then move to repose that danger, and they dance around the board in {{w|octagram}}ish 'circuits'.&lt;br /&gt;
::I would propose, though, that a limited-jump entry from two adjoining enclosures to land knights onto a 2x3 'shared enclosure' could work, such that they can't jump to any more thn their two opposite corners (thus also never jump out of it into the other's 'normal' enclosure). And, in my head, I'm imagning a form of zig-zagging diagonal that might extend the area without overlapping the (though intermingling, as with bishops) the viable landing zones. The following is a quick (and probably incorrect, if you spot the probable errors I've not handled correctly) method of mingling two sets of knights (1 &amp;amp; 2, mostly given free reign to top left and bottom right) between walls (#) and various other 'open' squares (.) that could be something else.&lt;br /&gt;
 2222###........&lt;br /&gt;
 2222#######....&lt;br /&gt;
 #2###21#####...&lt;br /&gt;
 #####122#1##..#&lt;br /&gt;
 #.####212######&lt;br /&gt;
 ....###221###1#&lt;br /&gt;
 .....###122#111&lt;br /&gt;
 ......###21##11&lt;br /&gt;
 .......#####111&lt;br /&gt;
 ........#.#1111&lt;br /&gt;
 .........###111&lt;br /&gt;
::In fact, with a narrower corridor, I believe I could constrain two sets of knights to travelling mutually non-antagonistically across a nominally intermingled diagonalised 'neutral-zone', ''plus'' send a viable 'bishop corridor' (in fact multiple bishop-corridors!) across in the other diagonal, but then it'd have to be a far less generous pseudo-shared area for the knights, and wouldn't look even as good as the above. [[Special:Contributions/172.68.205.123|172.68.205.123]] 00:11, 12 January 2025 (UTC)&lt;br /&gt;
:: You can have some interesting shaped-areas for knights too,  not just corridors; you can trivially put two knights together by blocking one of them from moving at all,  the interesting question is how to give them both the most freedom of movement, safely,  and/or the minimum number of 'blocks' for a given area. e.g. [https://output.jsbin.com/wegelanuci] [[User:JeffUK|JeffUK]] ([[User talk:JeffUK|talk]]) 11:24, 13 January 2025 (UTC)&lt;br /&gt;
:You can't have same-coloured knights also enter into an opposites-of-bishop shared space, because for all the wish to have shared (overlapping but not congruent) spaces for pieces of the same colour but different limitations, the presence of the anti-bishops would mean contention with the pro-knights.&lt;br /&gt;
:The fact tht the pawn-enclosures are totally without any same-set pieces (well, apart from the knight, but that was from a promotion) ''does'' seem to suggest there's a lack of possible mixing going on, I know. But, the way I read it, if heterochromic pieces can be 'mixed', then they can (which effectively is just the two different ecclesiastical compliments), with homochomic ones then also being allowed to mix if they can do so in a way such that they have ''all'' of an &amp;quot;A and B&amp;quot; area, an &amp;quot;A-only&amp;quot; area and a &amp;quot;B-only&amp;quot; area (it's a bit more complicated than that with the kings and queens, as they can traverse all of the same areas as each other, plus the lobe of knight-area which overlaps, but you have &amp;quot;knight+royal&amp;quot;, &amp;quot;royal-only&amp;quot; and &amp;quot;knight-only&amp;quot;).&lt;br /&gt;
:Though I ''can'' think of one such sharing-situation I would mark down as missed: i.e. a pawn sharing a space with bishops and/or knights with a bishop-/knight-proof corridor 'directly forward' (and, of course, no sideways movement allowed by the pawn), giving the pawn both its unique space and shared space and only-the-other-piece spaces off to the sides. Though, the whole promotion prospects means that just about anything could 'suddenly' be in the pawn-only space, thus sending potential knights/bishops into that 'by proxy'.&lt;br /&gt;
:...or maybe I've not extrapolated Randall's precise methodology here, but I believe I've accounted the general limitations he seems to have worked to. [[Special:Contributions/162.158.33.215|162.158.33.215]] 00:57, 11 January 2025 (UTC)&lt;br /&gt;
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I don't have permissions to upload an image to this wiki, but if anyone who does would like to copy it over, I illustrated each piece's range of movement here[https://pasteboard.co/64VsBMA5af8l.png]. [[User:D5xtgr|D5xtgr]] ([[User talk:D5xtgr|talk]]) 20:09, 10 January 2025 (UTC)&lt;br /&gt;
:I have put the picture in a [[3036:_Chess_Zoo#Trivia|trivia]] section --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 11:03, 12 January 2025 (UTC)&lt;br /&gt;
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The plan of the zoo looks like opposing Lewis Chess Men! [[User:Nicholasbailey87|Nicholasbailey87]] ([[User talk:Nicholasbailey87|talk]]) 23:28, 10 January 2025 (UTC)&lt;br /&gt;
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the transcript needs to be descriptive rather than a text-based diagram so it's screenreader accessible. if someone thinks it's necessary they can move the ascii art to the description. [[Special:Contributions/172.68.71.101|172.68.71.101]] 23:40, 10 January 2025 (UTC)&lt;br /&gt;
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A knight recently escaped. When asked for comment, the director of the zoo said &amp;quot;!?&amp;quot; [[Special:Contributions/172.68.70.134|172.68.70.134]] 01:07, 11 January 2025 (UTC)&lt;br /&gt;
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This is actually a sokoban chess puzzle, where the pieces can push the blocks. White to move and mate in 47.[[Special:Contributions/172.70.214.205|172.70.214.205]] 02:40, 11 January 2025 (UTC)NickM&lt;br /&gt;
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In the UK there is a famous zoo called &amp;quot;Chester Zoo&amp;quot;, comic readers from the UK will think there is a pun.--[[User:Doctormo|Doctormo]] ([[User talk:Doctormo|talk]]) 03:46, 11 January 2025 (UTC)&lt;br /&gt;
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In Russian, chess knights and bishops are literally called horses and elephants. [[Special:Contributions/172.71.148.59|172.71.148.59]] 10:40, 11 January 2025 (UTC)&lt;br /&gt;
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I don't think that the 'same portals that block bishops' can block knights, not without being longer.  A knight could get through the 'petting zoo' portal to the bishop paddock.  But there's another example below and to the left of a similar portal but much longer that DOES prevent the knights from passing. [[Special:Contributions/172.71.194.90|172.71.194.90]] 14:21, 11 January 2025 (UTC)&lt;br /&gt;
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Do I need new glasses or did the black king escape? [[Special:Contributions/162.158.95.97|162.158.95.97]] 17:15, 11 January 2025 (UTC)&lt;br /&gt;
:Look at the third visitor along at the 'top', then go straight down. Maybe less obvious as the dark pieces hide their internal details more, leaving just their fuzzy (depending on zoom level) outlines. [[Special:Contributions/172.69.79.164|172.69.79.164]] 21:10, 11 January 2025 (UTC)&lt;br /&gt;
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It looks like the transcript has switched the K's and Q's. The king is the piece with the cross on his crown. See {{w|Staunton chess set}}. --[[Special:Contributions/172.68.54.157|172.68.54.157]] 22:01, 11 January 2025 (UTC)&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361460</id>
		<title>3035: Trimix</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361460"/>
				<updated>2025-01-09T11:07:58Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: How on earth does Wikipedia not have an article on Lead Balloons ... BRB&lt;/p&gt;
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&lt;div&gt;{{comic&lt;br /&gt;
| number    = 3035&lt;br /&gt;
| date      = January 8, 2025&lt;br /&gt;
| title     = Trimix&lt;br /&gt;
| image     = trimix_2x.png&lt;br /&gt;
| imagesize = 436x259px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = You don't want the nitrogen percentage to be too high or you run the risk of eutrophication.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|Created by a FLOATING TRIMIX SCUBA DIVER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}&lt;br /&gt;
{{w|Trimix (breathing gas)|Trimix}} is a gas used in {{w|SCUBA}} tanks that consists of {{w|helium}}, {{w|oxygen}}, and {{w|nitrogen}}. Trimix comes in some standard ratios between the component gases, depending on the required diving depth, for example 21/35/44 (percentage oxygen/helium/nitrogen), 18/45/37 and 15/55/30 for increasing depth. Helium safely substitutes a portion of the nitrogen to minimize nitrogen's narcotic effects at greater depths, and to ease the effort required for breathing, as merely reducing the nitrogen ratio in an oxygen/nitrogen mix will increase oxygen to levels that, at the pressures that exist at depth, {{w|Oxygen toxicity|creates other dangers}} (hence why the Trimix ratios also provide slightly lower proportions of oxygen). This comic suggests that if the initial helium amount is too high, a diver will float away before reaching the water to start a dive, as their tank of air suddenly acts just like a sufficiently buoyant helium balloon. &lt;br /&gt;
&lt;br /&gt;
The reason a helium balloon creates lift is that it can inflate. The balloon has a thin and expandable layer, weighing almost nothing, that allows the intrinsically less dense gas to take up space at not much more than atmospheric pressure. The total weight of the filled balloon is less than the total weight of the air it displaces, thus creating {{w|buoyancy}}. A SCUBA tank is made of metal, is heavy and cannot inflate in normal (or near-normal) circumstances, which means it will never become lighter than the surrounding air as you pump more of ''any'' kind of gas into it. (In fact, it will just get heavier, as an inflating helium balloon does, but without the over-compensating increase in volume.) It will never be able to create any kind of lift, no matter the amount of helium (or any other mix of gas) that is compressed inside of it, and neither could a typical SCUBA tank even attain lift by thoroughly emptying it to try to create a {{w|vacuum balloon}}.&lt;br /&gt;
&lt;br /&gt;
The real reason SCUBA divers need to be careful with the amount of helium is to not get too little (or too much) oxygen for the intended depth and pressure, as well as reducing the troublesome nitrogen.&lt;br /&gt;
&lt;br /&gt;
The title text asserts that a trimix diver whose gas mix contains an excess of nitrogen runs &amp;quot;the risk of eutrophication&amp;quot;. The term {{w|Eutrophication|eutrophication}} describes the process by which nutrients (&amp;quot;fertilizers&amp;quot;) accumulate in an environment, typically a body of water, leading to consequences that are often unfortunate for inhabitants or users of that environment. The human body is an ecosystem, but one that is not typically subject to eutrophication, due to its manner of acquiring and jettisoning nutrients. Moreover, the nitrogen in trimix is diatomic elemental nitrogen, not the {{w|Nitrogen_fixation|&amp;quot;fixed&amp;quot;}} nitrogen that serves as a component of eutrophication. The diver would not breathe &amp;quot;fixed&amp;quot; nitrogen unless nitrogen-fixing bacteria were somehow incorporated into the SCUBA gear, a complex feature of dubious utility.&lt;br /&gt;
&lt;br /&gt;
[[Randall]] addressed the question &amp;quot;how much helium is needed to lift a human body&amp;quot; in a [https://what-if.xkcd.com/62/ What if?] article. Helium has also featured in comics [[2766: Helium Reserve]] and [[2972: Helium Synthesis]].&lt;br /&gt;
&lt;br /&gt;
The parameters required to make a lighter-than-air metal container have been explored in the context of the lead balloon,  concluding that a balloon made of even the thinnest metal foil would need to be at least 1 cubic metre in volume to lift even it's own weight.&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[In a single frame five images of Cueball is shown as a kind of a cartoon event sequence, with each image a later time in the process. The first image to the left shows Cueball standing by the shore of a body of water. He is wearing SCUBA gear, goggles, breathing tubes, SCUBA tanks with a small H logo on it on his back, and swimming flippers, which almost touch the water.]&lt;br /&gt;
&lt;br /&gt;
:[In the next four images he has the same equipment on, but with changes. It should be seen as he is still at the edge of the water, but that is not drawn in the next four depictions of Cueball.]&lt;br /&gt;
&lt;br /&gt;
:[In the second image  to the right of the first, Cueball's SCUBA tank is beginning to float upwards, so the end that is not teetered to Cueball move out and up, as shown with three small lines beneath the tank.]&lt;br /&gt;
&lt;br /&gt;
:[In the third image the SCUBA tank is now floating above Cueball's head and the strings pull his arms a bit upwards. Cueball has turned his head looking up at the tank floating above and behind his head. Again three small lines beneath the tank indicates it is moving upwards.]&lt;br /&gt;
&lt;br /&gt;
:[In the fourth image Cueball is now being lifted up, so his feet are now off the ground and he is tilting forward. The tank is now pointing it's bottom almost straight up and Cueball is looking down with his arms out the each side as the tank pulls him up. Two lines on either side of the tank indicate that it now wobbles above him as it lifts him up.]&lt;br /&gt;
&lt;br /&gt;
:[In the fifth and last image the SCUBA tank is now pulling a dangling Cueball high above the ground, above his head's height in the first image. The tank is now turned so it points it's bottom to the left with lines on either side indicating wobbling motion. Cueball is floating as lying prone a bit bended on the middle as the tanks straps pulls him up. At this point he yells:]&lt;br /&gt;
:Cueball: ''Help!''&lt;br /&gt;
&lt;br /&gt;
:[Caption below the panel:]&lt;br /&gt;
:Trimix SCUBA divers need to be careful not to let the helium percentage get too high.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
&lt;br /&gt;
[[Category:Comics featuring Cueball]]&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361459</id>
		<title>3035: Trimix</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361459"/>
				<updated>2025-01-09T11:05:46Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: fix {}s&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 3035&lt;br /&gt;
| date      = January 8, 2025&lt;br /&gt;
| title     = Trimix&lt;br /&gt;
| image     = trimix_2x.png&lt;br /&gt;
| imagesize = 436x259px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = You don't want the nitrogen percentage to be too high or you run the risk of eutrophication.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|Created by a FLOATING TRIMIX SCUBA DIVER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}&lt;br /&gt;
{{w|Trimix (breathing gas)|Trimix}} is a gas used in {{w|SCUBA}} tanks that consists of {{w|helium}}, {{w|oxygen}}, and {{w|nitrogen}}. Trimix comes in some standard ratios between the component gases, depending on the required diving depth, for example 21/35/44 (percentage oxygen/helium/nitrogen), 18/45/37 and 15/55/30 for increasing depth. Helium safely substitutes a portion of the nitrogen to minimize nitrogen's narcotic effects at greater depths, and to ease the effort required for breathing, as merely reducing the nitrogen ratio in an oxygen/nitrogen mix will increase oxygen to levels that, at the pressures that exist at depth, {{w|Oxygen toxicity|creates other dangers}} (hence why the Trimix ratios also provide slightly lower proportions of oxygen). This comic suggests that if the initial helium amount is too high, a diver will float away before reaching the water to start a dive, as their tank of air suddenly acts just like a sufficiently buoyant helium balloon. &lt;br /&gt;
&lt;br /&gt;
The reason a helium balloon creates lift is that it can inflate. The balloon has a thin and expandable layer, weighing almost nothing, that allows the intrinsically less dense gas to take up space at not much more than atmospheric pressure. The total weight of the filled balloon is less than the total weight of the air it displaces, thus creating {{w|buoyancy}}. A SCUBA tank is made of metal, is heavy and cannot inflate in normal (or near-normal) circumstances, which means it will never become lighter than the surrounding air as you pump more of ''any'' kind of gas into it. (In fact, it will just get heavier, as an inflating helium balloon does, but without the over-compensating increase in volume.) It will never be able to create any kind of lift, no matter the amount of helium (or any other mix of gas) that is compressed inside of it, and neither could a typical SCUBA tank even attain lift by thoroughly emptying it to try to create a {{w|vacuum balloon}}.&lt;br /&gt;
&lt;br /&gt;
The real reason SCUBA divers need to be careful with the amount of helium is to not get too little (or too much) oxygen for the intended depth and pressure, as well as reducing the troublesome nitrogen.&lt;br /&gt;
&lt;br /&gt;
The title text asserts that a trimix diver whose gas mix contains an excess of nitrogen runs &amp;quot;the risk of eutrophication&amp;quot;. The term {{w|Eutrophication|eutrophication}} describes the process by which nutrients (&amp;quot;fertilizers&amp;quot;) accumulate in an environment, typically a body of water, leading to consequences that are often unfortunate for inhabitants or users of that environment. The human body is an ecosystem, but one that is not typically subject to eutrophication, due to its manner of acquiring and jettisoning nutrients. Moreover, the nitrogen in trimix is diatomic elemental nitrogen, not the {{w|Nitrogen_fixation|&amp;quot;fixed&amp;quot;}} nitrogen that serves as a component of eutrophication. The diver would not breathe &amp;quot;fixed&amp;quot; nitrogen unless nitrogen-fixing bacteria were somehow incorporated into the SCUBA gear, a complex feature of dubious utility.&lt;br /&gt;
&lt;br /&gt;
[[Randall]] addressed the question &amp;quot;how much helium is needed to lift a human body&amp;quot; in a [https://what-if.xkcd.com/62/ What if?] article. Helium has also featured in comics [[2766: Helium Reserve]] and [[2972: Helium Synthesis]].&lt;br /&gt;
&lt;br /&gt;
The parameters required to make a lighter-than-air metal container have been explored in the context of the {{w|lead balloon}},  concluding that a balloon made of even the thinnest metal foil would need to be at least 1 cubic metre in volume to lift even it's own weight.&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[In a single frame five images of Cueball is shown as a kind of a cartoon event sequence, with each image a later time in the process. The first image to the left shows Cueball standing by the shore of a body of water. He is wearing SCUBA gear, goggles, breathing tubes, SCUBA tanks with a small H logo on it on his back, and swimming flippers, which almost touch the water.]&lt;br /&gt;
&lt;br /&gt;
:[In the next four images he has the same equipment on, but with changes. It should be seen as he is still at the edge of the water, but that is not drawn in the next four depictions of Cueball.]&lt;br /&gt;
&lt;br /&gt;
:[In the second image  to the right of the first, Cueball's SCUBA tank is beginning to float upwards, so the end that is not teetered to Cueball move out and up, as shown with three small lines beneath the tank.]&lt;br /&gt;
&lt;br /&gt;
:[In the third image the SCUBA tank is now floating above Cueball's head and the strings pull his arms a bit upwards. Cueball has turned his head looking up at the tank floating above and behind his head. Again three small lines beneath the tank indicates it is moving upwards.]&lt;br /&gt;
&lt;br /&gt;
:[In the fourth image Cueball is now being lifted up, so his feet are now off the ground and he is tilting forward. The tank is now pointing it's bottom almost straight up and Cueball is looking down with his arms out the each side as the tank pulls him up. Two lines on either side of the tank indicate that it now wobbles above him as it lifts him up.]&lt;br /&gt;
&lt;br /&gt;
:[In the fifth and last image the SCUBA tank is now pulling a dangling Cueball high above the ground, above his head's height in the first image. The tank is now turned so it points it's bottom to the left with lines on either side indicating wobbling motion. Cueball is floating as lying prone a bit bended on the middle as the tanks straps pulls him up. At this point he yells:]&lt;br /&gt;
:Cueball: ''Help!''&lt;br /&gt;
&lt;br /&gt;
:[Caption below the panel:]&lt;br /&gt;
:Trimix SCUBA divers need to be careful not to let the helium percentage get too high.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
&lt;br /&gt;
[[Category:Comics featuring Cueball]]&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361458</id>
		<title>3035: Trimix</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=3035:_Trimix&amp;diff=361458"/>
				<updated>2025-01-09T11:05:03Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: /* Explanation */  + Ref to lead balloon, the natural conclusion of this idea.&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 3035&lt;br /&gt;
| date      = January 8, 2025&lt;br /&gt;
| title     = Trimix&lt;br /&gt;
| image     = trimix_2x.png&lt;br /&gt;
| imagesize = 436x259px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = You don't want the nitrogen percentage to be too high or you run the risk of eutrophication.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|Created by a FLOATING TRIMIX SCUBA DIVER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}&lt;br /&gt;
{{w|Trimix (breathing gas)|Trimix}} is a gas used in {{w|SCUBA}} tanks that consists of {{w|helium}}, {{w|oxygen}}, and {{w|nitrogen}}. Trimix comes in some standard ratios between the component gases, depending on the required diving depth, for example 21/35/44 (percentage oxygen/helium/nitrogen), 18/45/37 and 15/55/30 for increasing depth. Helium safely substitutes a portion of the nitrogen to minimize nitrogen's narcotic effects at greater depths, and to ease the effort required for breathing, as merely reducing the nitrogen ratio in an oxygen/nitrogen mix will increase oxygen to levels that, at the pressures that exist at depth, {{w|Oxygen toxicity|creates other dangers}} (hence why the Trimix ratios also provide slightly lower proportions of oxygen). This comic suggests that if the initial helium amount is too high, a diver will float away before reaching the water to start a dive, as their tank of air suddenly acts just like a sufficiently buoyant helium balloon. &lt;br /&gt;
&lt;br /&gt;
The reason a helium balloon creates lift is that it can inflate. The balloon has a thin and expandable layer, weighing almost nothing, that allows the intrinsically less dense gas to take up space at not much more than atmospheric pressure. The total weight of the filled balloon is less than the total weight of the air it displaces, thus creating {{w|buoyancy}}. A SCUBA tank is made of metal, is heavy and cannot inflate in normal (or near-normal) circumstances, which means it will never become lighter than the surrounding air as you pump more of ''any'' kind of gas into it. (In fact, it will just get heavier, as an inflating helium balloon does, but without the over-compensating increase in volume.) It will never be able to create any kind of lift, no matter the amount of helium (or any other mix of gas) that is compressed inside of it, and neither could a typical SCUBA tank even attain lift by thoroughly emptying it to try to create a {{w|vacuum balloon}}.&lt;br /&gt;
&lt;br /&gt;
The real reason SCUBA divers need to be careful with the amount of helium is to not get too little (or too much) oxygen for the intended depth and pressure, as well as reducing the troublesome nitrogen.&lt;br /&gt;
&lt;br /&gt;
The title text asserts that a trimix diver whose gas mix contains an excess of nitrogen runs &amp;quot;the risk of eutrophication&amp;quot;. The term {{w|Eutrophication|eutrophication}} describes the process by which nutrients (&amp;quot;fertilizers&amp;quot;) accumulate in an environment, typically a body of water, leading to consequences that are often unfortunate for inhabitants or users of that environment. The human body is an ecosystem, but one that is not typically subject to eutrophication, due to its manner of acquiring and jettisoning nutrients. Moreover, the nitrogen in trimix is diatomic elemental nitrogen, not the {{w|Nitrogen_fixation|&amp;quot;fixed&amp;quot;}} nitrogen that serves as a component of eutrophication. The diver would not breathe &amp;quot;fixed&amp;quot; nitrogen unless nitrogen-fixing bacteria were somehow incorporated into the SCUBA gear, a complex feature of dubious utility.&lt;br /&gt;
&lt;br /&gt;
[[Randall]] addressed the question &amp;quot;how much helium is needed to lift a human body&amp;quot; in a [https://what-if.xkcd.com/62/ What if?] article. Helium has also featured in comics [[2766: Helium Reserve]] and [[2972: Helium Synthesis]].&lt;br /&gt;
&lt;br /&gt;
The parameters required to make a lighter-than-air metal container have been explored in the context of the {w|lead balloon},  concluding that a balloon made of even the thinnest metal foil would need to be at least 1 cubic metre in volume to lift even it's own weight.&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[In a single frame five images of Cueball is shown as a kind of a cartoon event sequence, with each image a later time in the process. The first image to the left shows Cueball standing by the shore of a body of water. He is wearing SCUBA gear, goggles, breathing tubes, SCUBA tanks with a small H logo on it on his back, and swimming flippers, which almost touch the water.]&lt;br /&gt;
&lt;br /&gt;
:[In the next four images he has the same equipment on, but with changes. It should be seen as he is still at the edge of the water, but that is not drawn in the next four depictions of Cueball.]&lt;br /&gt;
&lt;br /&gt;
:[In the second image  to the right of the first, Cueball's SCUBA tank is beginning to float upwards, so the end that is not teetered to Cueball move out and up, as shown with three small lines beneath the tank.]&lt;br /&gt;
&lt;br /&gt;
:[In the third image the SCUBA tank is now floating above Cueball's head and the strings pull his arms a bit upwards. Cueball has turned his head looking up at the tank floating above and behind his head. Again three small lines beneath the tank indicates it is moving upwards.]&lt;br /&gt;
&lt;br /&gt;
:[In the fourth image Cueball is now being lifted up, so his feet are now off the ground and he is tilting forward. The tank is now pointing it's bottom almost straight up and Cueball is looking down with his arms out the each side as the tank pulls him up. Two lines on either side of the tank indicate that it now wobbles above him as it lifts him up.]&lt;br /&gt;
&lt;br /&gt;
:[In the fifth and last image the SCUBA tank is now pulling a dangling Cueball high above the ground, above his head's height in the first image. The tank is now turned so it points it's bottom to the left with lines on either side indicating wobbling motion. Cueball is floating as lying prone a bit bended on the middle as the tanks straps pulls him up. At this point he yells:]&lt;br /&gt;
:Cueball: ''Help!''&lt;br /&gt;
&lt;br /&gt;
:[Caption below the panel:]&lt;br /&gt;
:Trimix SCUBA divers need to be careful not to let the helium percentage get too high.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
&lt;br /&gt;
[[Category:Comics featuring Cueball]]&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=2604:_Frankenstein_Captcha&amp;diff=230091</id>
		<title>2604: Frankenstein Captcha</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=2604:_Frankenstein_Captcha&amp;diff=230091"/>
				<updated>2022-04-11T09:31:19Z</updated>
		
		<summary type="html">&lt;p&gt;JeffUK: Definitely a tomato/ tomAto looking at the vines, and it is the archetypal fruit vs vegetable&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 2604&lt;br /&gt;
| date      = April 8, 2022&lt;br /&gt;
| title     = Frankenstein Captcha&lt;br /&gt;
| image     = frankenstein_captcha.png&lt;br /&gt;
| titletext = The distinction between a ship and a boat is a line drawn in water.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|Created by a CAPTCHA RATED ARGH-Please change this comment when editing this page. Do NOT delete this tag too soon.}}&lt;br /&gt;
&lt;br /&gt;
This comic strip is a play on the meanings (and misunderstanding) of the name &amp;quot;Frankenstein&amp;quot;.  ''{{w|Frankenstein; or, the Modern Prometheus}}'' is an 1818 novel by Mary Shelley about a medical student named Victor Frankenstein who creates an artificial life-form. The man he creates once describes himself as &amp;quot;the Adam of [Frankenstein's] labour&amp;quot; in the book, and strictly speaking is properly known as &amp;quot;Frankenstein's ''monster''&amp;quot; (or perhaps &amp;quot;creation&amp;quot; or &amp;quot;son&amp;quot;), but is often erroneously called &amp;quot;Frankenstein&amp;quot; himself. This has been fertile ground for many, many debates whether the monster could also properly be called &amp;quot;Frankenstein,&amp;quot; either as a family name, an honorific, or simply because it's more recognizable and convenient. Randall has weighed in on the debate himself in a previous comic, [[1589: Frankenstein]].&lt;br /&gt;
&lt;br /&gt;
The CAPTCHA shown in the comic instructs the user to select all tiles containing Frankenstein. The tiles include both a reanimated corpse resembling Frankenstein's monster and a scientist yelling, &amp;quot;It's alive!” who is clearly intended to be Victor Frankenstein. The problem arises from the contrast between various definitions of the term Frankenstein. Going just off the book's text, the monster has no name, so the correct answer to the CAPTCHA is just the left square of the third row.  However, the character depicted there is clearly ''Henry'' Frankenstein from the famous {{w|Frankenstein (1931 film)|1931 film adaptation}} (Victor Frankenstein never said the words &amp;quot;it's alive!&amp;quot; in the book), and likewise the creature depicted is clearly inspired by {{w|Boris Karloff}}'s iconic portrayal in that film and its sequels.  If the images are captured from that film, then all four of them could be said to be &amp;quot;containing (a subset of) ''Frankenstein'' (the 1931 film)&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
CAPTCHAs serve a dual purpose: (1) to separate human users from bots by way of intelligent interaction, and (2) to train a neural network, hence the &amp;quot;correct answer&amp;quot; to image recognition CAPTCHAs is not known ahead of time and is merely based on the most commonly-chosen tiles. Users who frequently face CAPTCHAs are familiar with the dilemma of having to choose tiles that they know do not contain the requested object but which they know were likely chosen by previous users, making the CAPTCHA one part object-identification exercise and one part human-psychology exercise. Thus, a user who knows that &amp;quot;Frankenstein&amp;quot; refers only to the scientist would face this CAPTCHA with dread, uttering &amp;quot;Oh No&amp;quot; as they realize that they must select the tiles containing the monster, and possibly not even be allowed to select the tile containing the actual scientist Victor Frankenstein if they want to pass the CAPTCHA.&lt;br /&gt;
&lt;br /&gt;
Alternatively, this comic strip with its &amp;quot;Oh No&amp;quot; caption could be referencing [[1897]], which would imply that someone had actually created a Frankenstein's monster which needs to be located as soon as possible.&lt;br /&gt;
&lt;br /&gt;
Many of the other tiles appear to be pictures of entities that inspire similar pedantry. For example, there is a picture of a turtle (or possibly a tortoise, or a reference to the {{w|Voight-Kampff_machine|Voight-Kampff test}} used in a manner analogous to CAPTCHA), a ship (or possibly a boat), {{w|Link (The Legend of Zelda)|Link}} (the name given to each of several protagonists that appear across generations and timelines, throughout the ''{{w|Legend of Zelda}}'' video games, who many erroneously refer to as Zelda), a pond (or possibly a lake, a puddle, or a {{w|mirage}}), a squash or pumpkin (often subject to the ''fruit or vegetable'' debate), an erupting volcano (with lava, or is it magma?), and the planet Pluto (or is it a dwarf planet?). Other tiles seem to be inspired by images that commonly occur in actual captchas, like the STOP sign or the traffic light. However, at least some of these may also be meant to fall into the category of entities that inspire pedantry, for example: because traffic lights can also be called traffic signals or stoplights; many people thinking that the shape of a stop sign is a hexagon, not an octagon; and the definition of a sandwich (previously discussed as a “random semi-ironic obsession” in [[1835]]). &lt;br /&gt;
&lt;br /&gt;
The title text refers to one of the methods used to differentiate a ship from a boat. When making a turn, if the vessel leans towards the inside of the turn circle then it is considered a boat, whereas if the vessel leans away from the turn circle it is considered a ship[https://www.youtube.com/watch?v=L1iM2CG5QQ8]. Since the vessel generates a wake as it moves, checking whether it is a boat or a ship can be done while it is literally drawing a line on the water (the wake). The phrase &amp;quot;a line drawn in water&amp;quot; is also an idiom for something ephemeral. Ironically, it has persisted for a long time and dates back at least to the early Buddhists. (e.g. [https://suttacentral.net/an3.132/en/sujato?layout=plain&amp;amp;reference=none&amp;amp;notes=asterisk&amp;amp;highlight=false&amp;amp;script=latin| AN 3.132] &amp;amp; [https://suttacentral.net/an7.74/en/sujato?layout=plain&amp;amp;reference=none&amp;amp;notes=asterisk&amp;amp;highlight=false&amp;amp;script=latin| AN 7.74]). The distinction between a ship and a boat is also unclear, having changed over time, with no universally accepted rule to {{w|Ship#Nomenclature|distinguish between the two}}. The title text is also a pun on the common idiom &amp;quot;drawing a line in the sand.&amp;quot;&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
{{incomplete transcript|Do NOT delete this tag too soon.}}&lt;br /&gt;
&lt;br /&gt;
:[A captcha design, with a header and four rows of four pictures each below it. The header, in white lettering on a blue background, reads:]&lt;br /&gt;
:To continue, please click&lt;br /&gt;
:All squares containing&lt;br /&gt;
:Frankenstein&lt;br /&gt;
&lt;br /&gt;
:[The pictures, all with gray backgrounds, are as follows, from left to right in each row:]&lt;br /&gt;
&lt;br /&gt;
Row 1&lt;br /&gt;
* Tortoise (or turtle)&lt;br /&gt;
* Ship (or boat)&lt;br /&gt;
* Frankenstein's monster (often mistaken as Frankenstein) waking up from a slab, while lightning strikes.&lt;br /&gt;
::Monster: GRRR&lt;br /&gt;
* Link from Legend of Zelda series (often mistaken as Zelda)&lt;br /&gt;
&lt;br /&gt;
Row 2&lt;br /&gt;
* Lake (or pond), possibly a mirage, in the Egyptian desert&lt;br /&gt;
* Megan (or Science Girl, or Danish--possibly a direct joke about this wiki)&lt;br /&gt;
* Lava (or magma)&lt;br /&gt;
* Tomato (fruit vs vegetable)&lt;br /&gt;
&lt;br /&gt;
Row 3&lt;br /&gt;
* A mad scientist (Victor Frankenstein) throwing a switch while lightning strikes outside&lt;br /&gt;
::Frankenstein: It's alive!&lt;br /&gt;
* Sandwich&lt;br /&gt;
* Stop sign&lt;br /&gt;
* Girl running away from Frankenstein's monster&lt;br /&gt;
::Girl: Monster!&lt;br /&gt;
&lt;br /&gt;
Row 4&lt;br /&gt;
* Rocket (spaceship) flying by Pluto (planet or dwarf planet)&lt;br /&gt;
* Cueball and Ponytail standing next to each other&lt;br /&gt;
* Traffic light (also called a stoplight, possibly mistaken as stop sign?)&lt;br /&gt;
* Frankenstein's monster&lt;br /&gt;
&lt;br /&gt;
:[Caption below the panel]:&lt;br /&gt;
:Oh no.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
[[Category:Comics with color]]&lt;br /&gt;
[[Category:CAPTCHA]]&lt;br /&gt;
[[Category:Fiction]]&lt;br /&gt;
[[Category:Animals]]&lt;br /&gt;
[[Category:Food]]&lt;/div&gt;</summary>
		<author><name>JeffUK</name></author>	</entry>

	</feed>